Primary Foul Sewer value engineering

The concept design for the Primary Foul Sewer (PFS) had 28 construction/access shafts at a maximum spacing of 100 metres. The designer of the Primary Foul Sewer network, challenged the standard design criteria, producing a designer’s risk assessment of operational activities (inspection/maintenance/repair) in support of a tender design comprising just 14 shafts at an average spacing of 145m.